package com.tuu.security;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.access.SecurityMetadataSource;
import org.springframework.security.access.intercept.AbstractSecurityInterceptor;
import org.springframework.security.access.intercept.InterceptorStatusToken;
import org.springframework.security.web.FilterInvocation;
import org.springframework.security.web.access.intercept.FilterInvocationSecurityMetadataSource;
import org.springframework.stereotype.Service;
import javax.servlet.*;
import java.io.IOException;
@Service
@Slf4j
public class MyFilterSecurityInterceptor extends AbstractSecurityInterceptor implements Filter {
//https://blog.csdn.net/weixin_34220179/article/details/85906596
    @Autowired
    private FilterInvocationSecurityMetadataSource securityMetadataSource;
    @Autowired
    public void setMyAccessDecisionManager(MyAccessDecisionManager myAccessDecisionManager) {
        super.setAccessDecisionManager(myAccessDecisionManager);
    }
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        log.info("执行到MyFilterSecurityInterceptor");
        FilterInvocation fi = new FilterInvocation(request, response, chain);
        invoke(fi);
    }
    public void invoke(FilterInvocation fi) throws IOException, ServletException {
//fi里面有一个被拦截的url
//里面调用MyInvocationSecurityMetadataSource的getAttributes(Object object)这个方法获取fi对应的所有权限
//再调用MyAccessDecisionManager的decide方法来校验用户的权限是否足够
        InterceptorStatusToken token = super.beforeInvocation(fi);
        try {
//执行下一个拦截器
            fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
        } finally {
            super.afterInvocation(token, null);
        }
    }
    @Override
    public void destroy() {
    }
    @Override
    public Class<?> getSecureObjectClass() {
        return FilterInvocation.class;
    }
    @Override
    public SecurityMetadataSource obtainSecurityMetadataSource() {
        return this.securityMetadataSource;
    }
}